Liquid fuel feeding mechanism



7, 1945- R. w. JOHNSON 1- AL 2,381,756

' LIQUID FUEL FEEDING MECHANISM- 4 Sheets-Sheet 1 Filed Feb. 14, 1942INVENTORY. F0 5 1M Jal /Mso/x BY CED/P/O E. ZARWHL fpv u ,MMSL

AT TO R N EY.

Agg. 7, 1945,

Filed Feb. '14, 1942 4 Sheets-Sheet 2 INVENTORSI- )Pos M/ Jam/50MTORNEY.

Aug. 7, 1945. R. w. JOHNSON ET AL 75 LIQUID FUEL FEEDING MECHANISM FiledFeb. 14, 1942 4 Sheets-Sheet s Aug. 7, 1945. 7' R..w. JOHNSON ET ALLIQUID FUEL FEEDING MECHANISM Filed Feb. 14, 1942 4 Sheets-Sheet 4 IINVENTORY. FPOV w J0///V50A/ CEDR/CI: zflRM/ELL ATTORNEY.

139.19. BY xk w wz.

Patented Aug. 7, 1945 UNITED STATES ATENT; oF I J a LIQUIDrunL iziiilinincfia lsfif Q A I A I Roy w. Johnson and Cedric E. Zarwell, Milwaukee, Wis., assignors to Automatic Products Company, Milwaukee, consinWis., a corporation of Wis- 11 Claims.

This invention relates to a liquid fuel feeding mechanism for burners ofthe type commonly called oil lifters, and wherein a motor-driven pump isemployed for pumping the oil or liquid fuel from a bulk storage tank, orother source of supply, to a receptacle having a liquid supply chamberand disposed adjacent to or constituted as a part of the burner.Ordinarily, the liquid fuel flows to the burner by gravity under thecontrol of suitable metering and control devices, such as the commonconstant level devices of the type shown and described in Patent2,068,138, granted January 19, 1937, to Roy W. Johnson, for Devices forcontrolling flow of fluid to oil burners and the like.

The object of the invention is to provide a liquid fuel feedingmechanism of thischaracter, which is simple, practical, and closelyorganizedin construction, reliable, safe, and efficient in operation,easy and comparatively inexpensive to manufacture, and capable of beingconveniently installed. Another object is to provide liquid fuel feedingmechanism of this character, and having these advantages, and which isso constituted and organized that its various elements are readilyaccessible for purposes of adjustment, replacement, or'repair. t J

Another object of th invention is to provide liquid fuel feedingmechanism. of this character, and having the foregoing advantages, andwhich embodies in its construction an automatically operable safetydevice, functioning to prevent flooding of the mechanism in the event offailure of main control of the pump motor.

In one form of the invention the safety device operates to effectautomatic returnof substantially all of the liquid from the liquid fuelsupply chamber of the fuel feeding mechanism'back to the bulk storagetank or source of supply ofliquid fuel. In an alternative or modifiedform of the invention the safety device varies the action of the pump sothat it merely recirculates rather than pumps the liquid fuel. In eitherinstance-the action is such that the-pump remains primed.

Another Object of the'invention is to. provide liquid fuel mechanism ofthis character, and having these advantages, and so constituted and.organized that the motor, while effectively controlled and protected,is also combined in a compact and advantageous manner with the pump soas not only to directly drive the same but to smooth out the action uponstarting of the motor and upon fluctuations in the load imposed thereon.

Other objects and advantages reside in certain novel features of theconstruction,arrangement,

section, taken on line 4-4 of Figure 5;

and combination of parts, which will be hereinafter more fully describedand particularly pointed out in the appended claims, reference being badto the accompanying drawings forming a partof this specification, and inwhich: l Figur 1 is a view partly in transverse, vertical cross section,and partly in elevation, illustrating a liquid fuel feeding. mechanismembodying'the present invention; a Figure 2 is a view in top plan onreduced-scale of the liquid. fuel feeding mechanism-shown in Figurel;'1- 1. Figure 3 is a ;view thereof inside elevationil.- lustrating howthe mechanism may be'supported ona wall or other suitable support; I.

Figure 4 is a view in transverse, horizontal cross Figure 5 isa viewpartly in side elevation and partly in vertical section, illustratingthe main control switchv for the motor, its operating, m ec h,-- anism,and the manner in which the main float is combined ,With theswitch-operating mechanism;

Figure 6 is a fragmentary detail viewl' ih section, takenon line lie- 6of Figure 5, looking in the direction of the arrows; N l

Figure 7 is a viewin top planfof .theliquidffuel feeding mechanismembodying thefinvention, with the cover, removed to illustratetheterminal board and the Way theleads or] conductors are combinedtherewith and with the pumpm'otor; Figure 8 is afragmentarydetailview,partlyin vertical cros section. and. partly invertical. side elevation, showingone of the motor supports) Figure 9 isa view inbottom plan of the, erminal board and switches carried thereby;Figure 10 is aview, in vertical cross section, taken online IDI0 ofFigure 9;

Figure 11 is ,a fragmentary view in vertical cross section, taken online l l -l l 'of Figure 9; FigureiIZ'is aview in top plan of 'tnepumphead of the rotarypump incorporatedintheliduiii fuelfeedingfsystemembodying the presentinvention; g Figure 13 is a viewtransverse cross taken on line I3--l3 of Figure 12'; V

Figure 14 is avi'ew inhorizontalcrosssection taken on line Hl-4of'1"igure [15; r

Figure 15 is a fragmentary view in vertical cross section, taken on linel 5 l 5 of Figure 14;

Figure 16 is a view in bottomplan of the" lower faceofthepumphead;

Figure '17 is a fragmentary view in'vertical cross section taken on-linellll of-Figure 12.; Figure 18 isa' fragmentary viewin 'top, plansection,

supply chamber 2 is provided with an outlet 3 equipped with an outletfitting 4 adapted to be connected by a suitable pipe line (not shown).to

the burner or to a constant level device of the type described in thepatent above referred to.

The top 5 of the receptacle l is provided with a central flanged opening6 surrounded by a gasket I.

A circular supporting plate 8 is provided and 'rests on the flange ofthe opening 6 and the gasket l. The supporting plate 8 is releasablysecured in position on the receptacle by means of screws 9 preferablythree in number (see Figure 7.). The screws 9 are threaded into the top5 of the receptacle l with their heads spaced from the upper surface ofthe top and they coact with keyhole slots l provided in the supportingplate 8 to perform the function of releasably securing the plate 8 inposition.

A rotary vane type pump, designated-generally as at H, is provided, andin the assembly is located within the suppl chamber 2 of thereceptacleland is positioned near the bottom of the supply chamber 2 so as, tobesubrnerged in the liquid fuel therein when the device is in operation.The pump l l comprises generally a pump head 12, the undersurface 12' ofwhich is machined or ground flat and plane to' adapt it to coact withcomplemental pump chamber forming members l3 and I4. The member I31 i inthe form of an annulus or ring and provides the peripheral wall of thepump chamber, whereas the member I4 is in the form of, a circular plateand provides one of the side walls .of the pump chamber, the other sidethereof being constituted by a portion of the under face'lz'of the pumhead l2. The pump chamber proper is. desi nated .at

IS. The ring or annulus l3 and circular plate 14 are disposedeccentrically to the central axis of the pump head so that thepumpchamber I is slightly eccentric to this axis. Screws and lock washers 16are extended through openings provided therefor in the members l3 and I4and are threaded into the pump head I 2 to releasably secure these partsassembled. A rotor .l! is rotatably fitted in the chamber l5. This rotorconsists of a disc of metal having a plurality of angularly spaced,transversely extending slots l8, extending out through the peripheryofthe rotor and being disposed at an angle to the radii of the rotor, asillustrated clearly in Figure 14. Sliding pump vanes 19 are fitted inthese slots and their outer edges wipe against theperipheral The pump isrigidly supported in position in the chamber 2 of the receptacle l, andthis may be conveniently accomplished by means of a plurality of,preferably three, hanger straps, designated generally at 23. Thesehanger straps 23 are of identical construction and are located at equalangulanintervals, about the pump head. The-upperflend of eachfhanger'strap 23 is inturned, as at 24, and is riveted or otherwise secured, asat 25, to the supporting plate. The lower end of each hanger strap isshaped and apertured toadapt it to be fastened to the pump head, thefastening being effected by screws 26. I 'I'he detail construction ofthe pump head is shownlinfFiguresl and 12 to 1'7, inclusive. The

under face l2 of the pump head I2 is formed with n. inlet groove 21 andan outlet groove 28,

both in open communication with the pump chamber; The outlet groove 28is also in open communication with an outlet passage 29, whichextends'entirely through the pump head I! and discharges into the liquidsupply chamber 2 of the receptacle l. The inlet groove 21 is in opencommunication with the lower end of an inlet passageway '30 whichinclines upwardly through a thickened portion of the pump head l2 andfreely communicates at its upper end with the chamber ill of a ballcheck valve '32 (see Figure l7) The ball 'check valve 32 'is' at thebottom of the chamber 3| and is engageable with a valve seat 33 providedin a vertical passage 34 which is in effect a continuation of thech'amber 3|. Access totheball check valve 32 and itsseat 33 is had'byvirtue ofthe provisionofa removable plug or closure 35 at the upper endof the chamber 3|. ThelOWerend of the,passage 34 communicates withthehoriiontalinlet passage 36 which extends over to andv is in opencommunication with a'vertic'alinlet passage 31.

' An oil supplyfpipe BB has its lower endfitted in this passage 3T andis securedand scaled to the wallsthereof by'a packinglnut or gland Thepipe 38 is preferablycopper tubing and its upper end is secured by'acompression coupling 40 to the inner end offan inlet nipple 4|; The

inlet nipple 4| is carried bya bracket 42 provided on the supp rtingplate 8 andisadapted to be connected to a pipe linefleading to a bulkstorage tank or other source of 'supplyof liquid fuel Which is locatedbelow the level of the .reccptacle I. v

: With this construction, when the rotor 20 of the pump is'rotated','the vanes |9,are forced outwardly under the influence ofcentrifugal force, and as they wipe past the inlet'groove 27, theypickup the oil supplied 'ther eto'through the oil supply pipe 38 andinlet passages 31, 36, 34,and 3'0, and theoil is carried around throughthe pump chamber. 15 and'is forced into the outlet groove 28 and upthrough 'the outletpassages "29 into the liquid supply chamber 2 of thereceptaclel.

An electric motor 45 is provided for driving the pump. The motor 45 maybe mounted in any suitable Way on and above the supporting plate 8.Asillu'strated in Figures '7 and 8, screws -46 may project from thehousing'in the-motor and extend through eyelets supported on elasticgrommetsor sleeves 48 carried by angle brackets 49 which'in turn arefixed to uprights 50 secured to and supported on the plate 8.

The motor is disposedwith its armature shaft 5| verticallyand'inalinement with the rotor shaft20 of'the pump. The lower end oftheannature"shaft'5 l,' which extends through an opening in the center ofthe plate 8, is slotted, as at 52, to receive a laterally extendingterminal 53 of a spring coupling 54. A similar laterally extendingterminal55 at the lower end of the spring coupling interflts at theslotted end 56 of a drive shaft 51. The lower end of the drive shaft 57is provided with a flattened por tion 58-that is, with a portion ofnon-circular cross section, and this flattened portion 58 of the shaft51 is interfitted with a correspondingly formed socket or axial opening59 of a coupling sleeve 68. A set screw 6| secures the coupling sleeveagainst accidental displacement off the lower end of the shaft. Thelower end of the coupling sleeve 60 is also provided with a socket 62which has a cross section corresponding to that of the upper end 22 ofthe flat rotor shaft 20 sothat when the socket 6| is slipped over theupper end of the rotor shaft, the rotor will be coupled to the driveshaft 51.

With this construction, when the motor 58 is running, the pump isdriven. On starting, and upon fiuctions in load, the spring coupling 54smooths out the action and relieves the motor of sudden shocks or loads.Another advantage of the construction thus .far described is that thebearing of the rotor shaftis automatically or self-lubricated.

The present invention proposes to intermittently or periodically run themotor 45 and operate the pump II to maintain the desired supply ofliquid fuel in the liquid supply chamber 2. Generally speaking, this isaccomplished by incorporating a suitable switch in the motor circuit,which, when closed, will complete the circuit and cause the motor torun, and which, when open, will break the circuitand stop the motor.This switch is in turn controlled by a float or other liquid levelresponsive means positioned in the liquid supply chamber and operativelyinterconnected with the switch to open and close the switch uponpredetermined rise and fall, respectively, of the liquid level in thesupply chamber 2.

In the construction. illustrated, a terminal board 64 is supported onthe uprights'Bll abovev the motor 45. A snap-acting toggle switch,designated generally at S, is carried by the under side of the terminalboard and is connectedin controlling relation in the circuit of theelectric motor 45.

This snap-acting toggleswitch includes 'a fixed contact, designatedgenerally at 65, the fixed contact 65 having a contact button 65'supported by a contact carrier strip which is secured to and supportedon, as well as in good electrical contact with, the terminal orbindingpost 61 carried by the terminal board 64. A movable contactbutton 88 is cooperatively related with the fixed contact button 66. t

Movable contact button 68 of the switch S is controlled by a togglemechanism of special construction. As illustrated in Figures 9 and 10,this toggle mechanism comprises stifily resilient toggle members T andT' constituted by portions of the one-piece metal stamping M. Thestamping M is stamped or punched out of a thin piece of spring steel orother appropriate metal of good electrical conductivity, and it isfashioned with side members and 10' cross connected at their ends bycross members H and 12. The end memher 1 l is tapered and apertured toadapt it to support and be fixedly connected to the shank of the movablecontact button 88, and also has a centrally disposed, inwardly directed,tapered and 10 are fixedly supported on though in spaced relation to.the underside of the terminal board 64 and this may be convenientlyaccomplished by bolts and nuts 13 and spacing sleeves 14, which alsoserve to secure a stop bracket 18 in position. One set of bolts and nuts13 is also employed to secure the contact clip 15' in position, thiscontact clip being provided at one end of a wire which, leads to oneterminal of the motor 45. The contact clip is thus in good electricalcontact with the metal stamping M, and consequently in electricalconnection with the movable contact .58. The toggle switch is completedby the toggle spring 11 compressed between spring cups l8 and (8,thebottoms of which are indented or socketed to adapt them to beinterfitted with the tapered projection I l of the toggle arm or memberT in the tapered end of finger 12 of the toggle arm T, respectively. Aswitch operator in the form of a strip ofinsulating material has aportion securely fixed by rivets 8| to the toggle armT' of the stampingM.

The other terminal of the motor is connected by a wire 82 to an angularbracket 83 secured by bolts and nuts 84 to the underside of the terminalboard. One of the screws 84 takes part in securing. the wire 82 to thebracket 83. The bracket'83 is constituted of metal of good thermalconductivity and its depending leg is fixedly secured to a leg 85 of theU-shaped bi-metallic strip or thermostatic leaf 88.- The other leg 81 ofthis leaf has a tapered end 88 and is provided with a. latching hole 89adjacent said tapered end 88. A contact 90 of springy material issupported by means of a bracket 9| on the underside'of the terminalboard and is adapted to have its outer end engage in the hole of the leg81 of the lei-metallic leaf 8! when normal temperatures prevail. When soengaged, however, the spring contact 90 is flexed or tensioned againstits inherent elasticity. If the motor heats up beyond a predeterminedpoint, the bi-metallic leaf 88 will warp under the influence of theincreased temperature so that the leg 81 thereof will move toward theleg 87 and pull the hole of the leg 81 off of the end of the springcontact 90 whereupon the spring contact 90 snaps clear of the bimetallicleaf and breaks the motor circuit. One side of the line is connected. bywire 92 to a binding post 92, which is in electrical contact with thebracket 9!, the latter being of material of good electrical conductivityand in direct electrical contact with the spring contact 90; The otherside of the line is connected by wire 93 to binding post 61. In otherwords, the snapacting toggle switch S and the thermal switch,constituted by the bi-metallic leaf 86 and the spring contact 90, areconnected in series in the motor circuit.

When normal temperatures are restored, the thermal switch may be readilyreset by means of a resetting plunger 95 supported in bearings providedtherefor in the supporting bracket 96 carried by the thermal board. Aspring 91 biases the plunger to its outer inoperative position, but itmaybe manually pressed inwardly against the action of this spring tocause it to engage the spring contact 90 and press the same inwardlywhereupon the end of the-spring contactcoac'ts with theincl ined end 88of thelegfll of the bimetallic leaf to cam the same toward the leg 85until the end of the spring carrier-90 is alined with the notch.Thereupon the leg 81 springs backso that the notch receives and latchesthe spring contact 90 in the closed position of the switch. 7

For the purpose of automatically operating the snap action toggle switchS, operating mechanism is provided therefor and includes a verticallyrec'iprocable switch operator I which may be in' the form of a rod whichis guided for vertical movement guidejbrackets IOI, I02 carried by thethermalboard and a supporting plate, respectively. Two adjustable-abut-ments or collars I03 and I04 are threaded on'the upper end of therod and are held inadj-ustment by a spring I05 interposed between them.A spring I06 may be interposed between the lower abutment in the guidebracket IN to counterbalance the weight of the operating mechanism."Thelower end of the switch operator 100 is pivotallycon-nected with theintermediate portion of a switch open atin'g lever I01. One end'of thislever isful cru-med, as at Ill-B, on the supporting plate 8 and theoppositeend connects with the end of an elongated link I09. The lowerend of this link I09 is interconnected with the float H0 in a specialmanner now tobe described.

'The float I I 0'has a heat arm II-I ailixed thereto. 'I he outer-end ofthis-float arm IiI isenlargedtha't is. the float arm is substantially Tshaped. A pair of links are employed as interconnecting means betweenthe neat arm and the link I 09. The upper of these links is designatedat M2, the lower at I I3. Each link is 'fulcrumed at one end, asindicated at M4, on a fulcrum bracket- I I 5 carriedby one of theliangerstraps; The opposite end of each link is pivotalh connec'ted to theenlarged outer end of the iloat'arm, as indicated at 1 I 6; The partsare so proportionedand dimensioned that the distance 'between the fuleraof thelinks H2 "and -I"I3 is greater than the distance betweenthe'irpivotal connections of the float arms. fThe lower end of the' link N59is *pivotally interconnected with an intermediate portion or the upper'linki'l2. With this link --arrangement between the float arm and thelink I09, the float I10 may move through a substantial distance upanddown, and yet it does not move laterally to any appreciable extent butwill move approximately along a vertical rec tilinear-pa'th. Theadvantages of this is that the requisite i'ioat travel may be had in avery 'com-' pact construction without the float engaging the drive shaftor coming into engagement with any at its opposite end with avertical'pass'age I2'I extending up through the top of the pump head.The upper "portion of this vertical passage lZI is internally threadedto receive the lower threaded end-of the valve body I22. The valve bodyI22 has an opening I23 extending axially thereassume through andalsoitransverse openings I 24.opening into the supplychamberf-Just'below the transverse openings 1-24 the valve body is provided wi-thavalve seat-I25. A needle-valve is slidably fitted in longitudinalopeningof the valve body and its lower point or tapered end cooperateswith the Valve seat I 25. The valve is normally closed but isautomatically-opened by a safety float I on the rise of liquid level inthe supply chamber to a predetermined degree. The float I30 has a floatarm -I3I fixed thereto and is freely pivoted or fulcruined on a suitablesupport, as indicated at I 32. -A link I 34 has its upper endconnectedto the float arm I8I and its lower end pivotally connected toacollar I35 fixed to the upper 'end of the needle valve.

A light coil spring 136 may be provided to counterbalance the weight'ofthe 'float, its arm; and link. When the main float fails, and the floatI30 is buoyed up, it pulls the valve I 25 off of its seat and since thebulk storage tank or main source of supply of liquid fuel. is located ata level lowerthan that of the liquid supply tank 2, the liquid in thetank will automatically siphon back to the bulk storagetank or mainsource of supply of liquid fuel through the valve body I22 through thepassages I2I, and the supply line 30.

While the siphoning of the liquid fuel back to the main source ofsupply, when the safety device is thrown into "action, is desirable inmany instances, substantially the same results may be obtained byvarying the construction of the pump head in such manner that instead ofthe siphoning action the pump may be caused to merely recirculate theliquid fuel. For example, as illustratedin Figures 18 and 19, the pumphead, designated at IZa, and corresponding in the main to the pump headI2, may be so constructed that the passage I20 is eliminated, and inlieu of the passage I20, a passage I20a may be provided. The passageI20a extends at an angle from the bottom of the vertical passage I2I "tothe upper portion of the chamber 3I. In other words, the passage I20acommunicates with the chamber 3I above the ball check valve 32. Withthis construction, when the safety valve I26 is opened, thev pump merelyrecirculates the liquid fuel in the supply chamber'Z.

The device is illustrated as being embodied in the type which has itsown receptacle, although,

of course, the receptacle may be constituted as a part of the burner.Where a separate receptacle is utilized, then it is usually equippedwith suitable mounting means. This may consist of a split clamping bandI40 having outturned aperture lugs M1 at its ends. These lu s areadapted to be alined with openings provided'in the side members ofa'bracket I42, andt besecured thereto by boltand nut I43. The bracket.I42 .may be attached by screws-I44, .or other suitable fastening meanaona wall or stationary support, in the manner illustrated in Figures 2 and3. I It is also usually desirable to .provide a cap or cover I-45 forthe 11101501 and terminal board, and such. cap or cover is releasablysecured .in place by tightening up clamping screwsfli can ried-bybrackets I48 rigidly attached tothe supporting plate 8 and coasting withslots I49 providedv in the cap or; cover. .The wires '92 and}; may becombined into a: same I50 equipped with a plug I 5I ladapted'tobeplugged into a Wall socket. 1 V

While we have shown and described one construction inwhich theinventionmay be advan tageously embodied, it is 'to be understood that theconstruction shown has beenselected merely for the purpose ofillustration or example, and that various changes in the size, shape,and are rangement of the parts may be made without de parting from thespirit of the invention or the scope of the subjoined claims.

Iclaim: J l y l l. A liquid fuel feeding mechanism adapted to beassembled with a receptacle for liquid fuel and comprising a pumpdepending into the receptacle and submerged in the liquid fuel therein,said pump having an inlet connected with a source of supply of liquidfuel and having an outlet-discharging into' said receptacle, an electricmotor supported exteriorly of the receptacle and having a drivingconnection with said pump, means responsive to changes of liquid levelin said.receptacle to control the action of the motor 'so as to cause asupply of liquid to be maintained in said receptacle, there being a ventintermediate the inlet to the pump and the source of supply of liquidfuel, said vent opening into said re.-. ceptacle, a valve biased toclosed position and normally closing said vent, and means actuated uponrise of liquid in the receptacle above a pre determined level to opensaid valve.

2. A liquid fuel feeding mechanism adaptedto be assembled with areceptacle for liquid fuel and comprising a rotary pump including a pumphead and cooperable pump chamber forming members, a rotor in said pumpchamber, means support-e ing said pump within the receptacle andsubmerged in the liquid fuel therein, said pump head having an inletleading to the pump chamber and an outlet leading from said chamber tothe interior of the receptacle, a suction line connected to said inletand communicating with a source of supply of liquid fuel disposed at alower level than the receptacle, an electric motor 113V? ing a drivingconnection with the rotor of said pump, means responsive to changes ofliquid level in said receptacle to control the action of the motor so asto cause a supply of liquid to be maintained in said receptacle, saidpump head having a vent opening interposed between the suction line andthe inlet of the pump, a valve normally closing said vent opening, and asafety float disposed in the receptacle and connected to the valve andoperable to open the valve upon riseof the liquid in said receptacleabove a predetermined level, whereupon liquid is syphoned from thereceptacle back to the source of supply thereof.

3. A liquid fuel feeding mechanism adapted to be assembled with areceptacle for liquid fuel and comprising a rotary pump including a pumphead and cooperable pump chamber forming members, a rotor in said pumpchamber, means supporting said pump within the receptacle and submergedin the liquid fuel therein, said pump head having an outletcommunicating with the interior of the receptacle and also having inletpassages communicating at one end with the pump chamber, a suction lineconnected to the other end of said inlet passages and communicating witha source of supply of liquid fuel disposed at a lower level than thereceptacle, an electric motor having driving connection with the rotorof the pump, means responsive to changes in liquid level in saidreceptacle to control the action'of the motor so as to cause a supply ofliquid to be maintained in said receptacle, said pump head having a ventpassage communicating with an intermediate P rtion of the inlet passagesat one end and with the interior of the receptacle at its other end, avalve normally closing said vent passage, a safety float disposed in thereceptacle and connected to said valve and operable to open the sameupon-rise of liquid in said receptacle above a predetermined level,whereupon liquid is syphoned from the receptacle back to the source ofsupply thereof, and a check valve incorporatedin the inlet passage inbetween the point of their communication with the pump chamber and thepointof communication of the vent passage therewith, whereby to maintainthe pump primed after occurrence of said syphoning action.

4. A liquid fuel feeding mechanism adapted to be assembled with areceptacle for liquid fuel having an opening in its top and comprising asupporting plate adapted to be mounted on the receptacle and to providea closure for said opening,'a rotary pump including a pump head and.cooperable pump chamber forming members, said members and said pumphead being detachably secured together, a rotor in said pump chamber,hangers supporting the pump head from said plate so that the pump, inthe assembly, is disposed in the lower portion of the receptacle, saidpump head having an inlet leading to the pump chamber and an outletleading from the chamber into the interior of the receptacle, a suctionline connectedto said inlet and communicating with a source of supply ofliquid fuel, an electric motor mounted on the top of the supportingplate and coaxially disposed with respect to the rotor of the pump,shaft and coupling means providing a driving connectionbetween the motorand the rotor of the pump, and means responsive to changes of liquidlevel in said receptacle to control the action of the motor so as tocause a supply of liquid to be maintained in said receptacle. i

5. A-liquid fuel feeding mechanism adapted to be assembled with areceptacle for liquid fuel having an opening at its top and comprising asupportingplate mounted on the receptacle and providing a closure forsaid opening, a rotary pump including a pump head and cooperablepumpchamber forming members, said members and said pump head beingdetachably secured together, a rotor in said pump chamber, hangerssupporting said pump from said plate, said pump head having an inletleading to the pump chamber and an outlet leadingfrom the chamber intothe interior of the receptacle, a suction line connected to the saidinlet and communicating with a source of supply of liquid fuel disposed.at a lower level than the receptacle, an electric motor mounted on thetop'of the plate and coaxially disposed with respect tothe pump, shaftand coupling means providing a driving connection between the motor andthe rotor of the pump, means responsive to changes of liquid level insaid receptacle to control the action of the motor so as to cause asupply of liquid to be maintained in said receptacle, said pump headhaving a vent opening interposed between the suction line and the inletof the pump chamber, a valve normally closing said vent opening, and asafety float disposed in the receptacle and connected to said valv andoperable to open the valve upon rise of the liquid in said receptacleabove a predetermined level whereupon liquid is syphoned from thereceptaclev back to the source of supply thereof.

6. In combination with a receptacle for liquid fuel, a rotary pumpsubmerged in the liquid fuel in said receptacle, said pump having aninlet connected with a source of supply of liquid ifuelzand an outletdischarging into said receptaclaanelectric motor :coaxially disposedwith respect to 'said pump, shaft and coupling means :providinga:driving connection 'between'said motor anw aidpump, a circuit for themotor, a switch incorporated .in said :circuit for :opening and closingthe same, a floatdisposed in the lower portion .Ofithe receptacleand-extending part way around said shaft and coupling means, a T-shapedfloat arm fixed to the float, apair-of links swingable "about spacedfixed fulcra, and having their ends opposite their fulcra pivoted to theends of the cross member of the float arm, and a connection betweenoneof said links and said switch,v

7. In combination with a receptacle for liquid fuel havingian opening inits top, liquid fuel feeding mechanism comprising a support mounted'onthe receptacle above the opening thereof, a rotary pump suspended fromthe support'and submerged in the liquid fuel in said receptacle, saidpump having an inlet connected with a source of supply of liquid fueland an-outlet discharging into said receptacle, an electric motormounted on the top of the supportand coaxially disposed with respect tosaid pump, shaft and coupling means providing a driving connectionbetween said motor and said pump, a circuit for the motor, a terminalboard supported above the motor, a snap action toggle switch carried bythe underside of the terminal board, a reciprocable operator .for theswitch, a switch operating lever having one end fulcrumed on the supportand having an intermediate portion connected to said reciprocable switchoperator, a floatdisposed in the receptacle to one side of said shaftand coupling means, a T-shaped float .arm fixed to the float, a pair ioflinks swingable about spaced fixed fulcra,- and having their endsopposite their .fulcra pivoted to the ends of the cross member ofthe-floatarm, the distance between the fulcra of the links bein greaterthan the distance between their pivotal connections with the float arm,and an elongated link having one end connected to the leg of theT-shaped float arm and its other end connected to the switch operatinglever.

8. A liquid fuel feeding mechanism adapted to be assembled with areceptacle for liquid fuel and comprising a rotary pump having a pumpchamber, a rotor in said pump chamber, means supporting the pump withinthe receptacle and submerged in the liquid fuel therein, saidpump havingan inlet leading to the pump chamber and an outlet leading from saidchamber to the interior of the receptacle, a suction line connected tosaid inlet and communicating with a source of supply of liquid fueldisposed ata lowerlevel than the receptacle, a motor having a drivingconnection with the rotor of the pump, means assures ing interposedbetween the suction line and the inlet "to the pump, a valve normallyclosing said vent opening, and a safetyifioat disposed in the receptacleand connected to the valve and operable to open the valve upon rise ofthe liquidin said receptacle above a predetermined level whereuponliquid is siphoned from the receptacle back to the source of supplytherein.

9. A liquid 'fuel feeding mechanism adapted to :be assembled with thereceptacle for liquid fuel and comprising a pump depending in thereceptacle and submerged in the liquid fuel there-v in, said :pumphaving an inlet connected with a source 'of supply of liquid fuel andhaving an outlet discharging into said receptacle, a motor for drivingthe pump, means responsive to changes of liquid level in said receptacleto control the action of the pump so as to cause a supply of liquid fuelto 'be maintained insaid receptacle, said pump having a passageintermediate its.in-, let and :its connection with the source of supplyand opening into the interior of the receptacle, a valve normallyclosing said passage, and means actuated upon rise of liquid in thereceptacle above a predetermined level and connected to the valve so asto automatically-open the valve upon rise of the liquid in thereceptacle to a point above-said predetermined level whereupon the pumpmerely effects recirculation of the liquid fuel in the receptacle.

10. In a device for maintaining a supply of liquid,a receptacle for theliquid, a rotary ,pump in the receptacle and including a pump headhaving an-inlet and an outlet therein and members dependent .from thehead and forming a pump rotor chamber below the pump head, a conduitconnectingthe inlet with a source of liquid exteriorly of thereceptacle, thepump head having an opening into the receptacleintermediatethe inlet and the conduit, a valve biased to close theintermediate opening, means responsive to rise in liquid level 'in thereceptacle beyond a predetermined amount and acting to open the valve, amotor drivingly connected withthe pump rotor, and means for controllingoperation of the motor responsive to a rise in the liquid level in thereceptacle.

1 1. In a liquid feeding mechanism, a receptacle having an outlettherefrom, a rotary pump in "the receptacle for discharging thereinto,said pump comprising a pump head formed with inlet and outlet openingstherein and forming a cup-like pocket about the outlet opening whereby areserve of liquid is always maintained in the pocket for priming thepump and animperforate member forming a pump :rotor chamberv incooperation with and below the head, :a conduit connecting the inletopening with a source of liquid, a motor driving the pump rotor, andmeans responsive to changes inthe liquid level in the receptacle forcontrolling operation of the motor.

- i ROY .W. JOHNSON.

CEDRIC E. ZARWELL.

